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1.
After the single-strain abilities of organic-pollutant-degrading bacteria in bioremediation of sediment environment of shrimp culture are determined, the multistrain degrading effect of the compositions of different strains is measured. The results indicate that the multi-strains groups have higher degrading ability than the single-strain groups. Three-strain groups are better than two-strain groups, and fourstrain groups are better than three-strain groups and five-strain groups, the groups composed of strains Lt7222, Lt7511. Fc6308 and Gy7018 has the best degrading effect, the CODMn removal rate is 73.2 % in 66 h, and gets to 82.7% in 114 h. 30% higher than that of the best single-strain group; Groups of Lt7222. Lt7511. Lt7451 and Gy7018 are the second, whose CODMn removal rate is 82.1% in 114 h. It is suggested that multi-species bacteria be used as thnctional bacteria in bioremediation of mariculture environment. 相似文献
2.
Characteristics of Water and Sediment Exchange Between Yangtze Estuary and Hangzhou Bay 总被引：1，自引：0，他引：1
Based on the 2-D flow and sediment numerical model of the Yangtze Estuary and the Hangzhou Bay, the characteristics of water and sediment exchange in their joint waters is studied through quantitative calculation and analysis of the characteristics of water flow and sediment transportation. The results show that there is periodical water and sediment exchange in this joint waters, that the net water exchange appears mainly between 0～6 m depth (theoretical datum plane, the same below) offshore and the maximum is near the depth of 2 m, and that the net sediment exchange mainly appears between 0～5 m depth and the maximum is near the depth of 3 m, indicating that the range of water flow passage is different from that of sediment transport from the Yangtze Estuary to the Hangzhou Bay. Combined with the results of numerical simulation, this paper also analyzes the hydrodynamical mechanism influencing water and sediment exchange between the Yangtze Estuary and the Hangzhou Bay, including tidal fluctuation, tidal current kinetic energy, tide-induced residual current and the trace of water particles. Finally, the sediment transportation passage on the Nanhui tidal flat is discussed, and the results show that sediment is transported into the Hangzhou Bay from the south side of Shipilei, while sediment is brought back to the South Channel of the Yangtze Estuary from the north side. 相似文献
3.
On the basis of accelerator mass spectrometer radiocarbon （AMS ^14C） dating, sedimentation rates of 11 cores collected from the northern to southern Okinawa Trough are discussed. The sedimentation rates in the Okinawa Trough roughly range from 11 to 39cm/ka, and the average is 23.0cm/ka. China＇s continental matter is the main sediment source of the middle Okinawa Trough and has important contribution to the northern and southern Okinawa Trough. The sedimentation rates during the marine oxygen isotope （MIS） 2 are uniformly higher than those during MIS 1 in the northern and middle Okinawa Trough while they are on the contrary in the southern Okinawa Trough. Sedimentation rates in the Okinawa Trough can be one of the proxies of sediment source and an indicator of cooling events. 相似文献
4.
Chemical forms of phosphorus in the sediments of the Daya Bay, the Zhujiang River estuary, and the Xiamen Bay are measured with extraction solutions of MgCl2, NaOH, and HCl. Their availabilities to Chlorella sp. and Isochrysis galbana are estimated by using sediments as the sole source of P in the bioassays. The results show that the contents of total phosphorus (TP) in these sediments are 449.3, 650.1 and 643.9 mg/kg, respectively. The contents of non-apatite inorganic P (NAIP) extracted with MgCl2 and NaOH from 3 sediments are 168.8, 146.6 and 118.1 mg/kg,respectively, and account for 18.3%～32.6% of TP. The phosphorus extracted with HCI solution is greater than that extracted with NaOH solution and the lowest extracted P is MgCl2-extractable P. The greatest relative growth rates of Chlorella sp. and Isochrysis galbana cultured with sediments are in the range of 4.3%～26.9%. The increasing biomasses of these algae correspond to NAIP and AAPP (the estimated algal-available particulate P). AAPP accounts for 42.4%～78.2% of NAIP, 21.1%～27.1% of total inorganic P, and 11.8%～20.3% of TP, respectively. 相似文献
5.
In a grid investigation, dinoflagellate cysts were collected from sediments in Xiamen Western Harbor in May of 2000, from which five species of cysts were identified: Alexandrium tamarensis, A. minutum, Lingulodinium polyedra, Gonyaulax scrippsae and Gymnodinium catenatum, account for about 21% in the species composition. The quanti-tative analysis of the sediments shows that the number of dinoflagellate cysts varies from 51 to 256 cysts/g of sediment, the highest value (>200 cysts/g) being recorded at the stations of the central part of the bay, while the lowest (<100 cysts/g) at the bay mouth. A good linear relationship is found between cyst amount and fine-grained sediments. Complex physiognomies on the seabed, topographty in the bay and weak water exchange are the main factors not only in cyst accumulation but also in their distribution pattern, and have resulted in the difference in cyst densities between the inner bay and the outer bay in the harbor. 相似文献
6.
Distribution and dispersal pattern of clay minerals in surface sediments, eastern Beibu Gulf, South China Sea 总被引：3，自引：2，他引：1
Clay minerology of sediments are useful in determining distribution,sources and dispersal routes of fine-grained sediments.In the present paper,clay minerals of surface sediments throughout the eastern part of Beibu Gulf has been investigated to reveal sources and transport of detrital finegrained sediments.Four distinct clay mineral suites were observed from cluster analysis of clay mineral compositions of the samples.From the distribution pattern of clay minerals,we conclude that kaolinte in the eastern gulf is mainly derived from South China Landmass;Smectite could not be transported mainly by surface current from north-western Hainan Island,and maybe minor portion of it from Red River;Illite is mainly transported by the currents from South China Sea.Chlorite has two sources,namely South China Sea and South China Landmass.The Zhujiang River derived sediments could not be one of the sources for the clay mineral here,because of very different composition and ratios.The distribution pattern of clay minerals in the eastern Beibu Gulf is mainly controlled by fine-grained sediment source and local currents.The Silt/Clay,Smectite/Kaolinte,and Smetite/(Chlorite+Illite) ratios could be used as indicators of fine-grained sediment dispersal in the gulf. 相似文献
7.
Observations of fluid mud were made in the lower North Passage of the Yangtze Estuary in February 2000, on 10 -11 August 2000, on 30 - 31 August 2000 (after two strong typhoons), on 21 - 24 August 2000 (neap tide) and on 3 -6 September 2000 (mean tide) respectively. In situ data show that the fluid mud in this area consists of fine cohesive sediment (median size 7.23 μm). The formation and movement of fluid mud varied during the neap-spring and flood-ebb tidal cycle. Observations suggest that fluid mud phenomena in this area may be categorised in a three-fold manner as slack water, storm and saltwedge features. The thickness of the fluid mud layer of slack water during the neap tide ranged from 0.2 to 0.96 m, whereas during the mean tide, the thickness ranged from 0.17 to 0.73 m, and the thickness of the fluid mud layer was larger during slack water than at the flood peak. Shoals cover an area of 800 km^2 with a water depth smaller than 5 m. Erosion of these extensive intertidal mudflats due to storm action provides an abundant sediment source. This is particularly significant in this estuary when the tidal level is lower than 5 m. The lower North Passage is a typical zone of saltwater wedging, so the saltwedge fluid mud has the most extensive spatial range in the estuary. 相似文献
8.
1Introduction The sediment dynamics of intertidal flats in-volves erosion, transport, and settling processes. A-mong these, the mechanisms of sediment transportare a key question. Progress has been made in awide range of associated areas, including sedime… 相似文献
9.
The major and minor element contents in the sediment core H9 from the hydrothermal fields of the Okinawa Trough show a sharp change at the depth of 80 cm. The elements enriched in the upper 80 cm core are those enriched in the hydrothermal deposits and in the surface sediments recovered from the hydrothermal fields in the trough, which indicates the input of hydrothermal materials. Comparing with other hydrothermal sediments from Mid-ocean Ridges or the Lau Basin, the degree of the enrichment of elements iron, copper,cobalt, and nickel is relatively low. However, the enrichment of elements manganese, lead, arsenic, antimony and mercury is remarkable. The average contents of these elements in the upper 80 cm core sediments are three to six times those in the lower section, and 3~12 times those in the surface sediments which are not influenced by hydrothermal activities. Hydrothermal activities have contributed significant manganese, lead, arsenic, antimony and mercury to the sediments, and these elements are distinct indicators for the hydrothermal activity in the Okinawa Trough. The significant enrichment of these elements in Core H9 upward from the depth 80 cm indicates the start or the significant enhancing of the hydrothermal activity in this area at about 5 740 aB.P. The average accumulation rate of manganese during this period is about 40 461 μg/(cm2·ka), which is similar to the hydrothermal sediments in the Lau Basin or the East Pacific Rise. 相似文献
10.
黄河口地区沉积物中若干地球化学参数及地球化学环境 总被引：5，自引：0，他引：5
This paper is concerned with the distibuticn of seme geochemical factors in sediments from Huanghe River Estuary，such as Eh,pH,Fe/Fe and the ratio of elementsp which show the characteristics of sedimentation in the estuary.According to the physical-chemistry principle the diagram of FeS2-Fe3O4-Fe2O3 system is made to indicate the coexistence and the tranform among minerals. 相似文献
11.
大洋富钴结壳成因机制的探讨——水成因证据 总被引：3，自引：0，他引：3
根据对大洋富钴结壳的分层与年龄、分层与生长速率、生长间断等观测事实,以及大洋富钴结壳主量元素锰、铁元素及钴元素、铂元素、稀土元素、氦同位素、锇同位素等的水成富集,指出大洋富钴结壳是水成因的,进而指出富钴结壳的形成与基岩无关,水动力条件、最低含氧带、生物作用等可能对富钴结壳的形成有控制作用。同时,富钴结壳不一定只生长在岩石裸露的海山上,在沉积物覆盖的海山区也有可能找到富钴结壳。 相似文献
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13.
A. G. Rodnikov A. G. Gainanov B. V. Yermakov V. M. Kovylin V. A. Seliverstov Ya. B. Smirnov P. A. Stroev Yu. K. Shchukin T. Kato H. Shimamura 《Marine Geophysical Researches》1985,7(3):379-387
The paper presents the results of geological-geophysical research carried out during the Soviet-Japanese cooperative study of the structure and dynamics of the Earth's crust and upper mantle in the transition zone from the Pacific Ocean to the Asian continent. The 300 km deep geological-geophysical section of the tectonosphere (geotraverse) has been compiled on the basis of combined interpretations of seismic, geological, petrographic, gravimetric, magnetometric, electromagnetic and heat flow measurements. Estimates were made of deep temperatures along the geotraverse and of the depths of the partial melting level that can be identified with the upper boundary of the asthenosphere. 相似文献
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15.
LAGFD-WAM numerical wave model——Ⅰ. Basic physical model 总被引：4，自引：1，他引：4
The LAGFD-WAM wave model is a third generation wave model. In the present paper the physical aspect of the model was shown in great detail including energy spectrum balance equation, complicated characteristics equations and source functions. 相似文献
16.
The apparent solubility product of calcite was measured by saturometry as a function of temperature and salinity. Simplified equations for the carbonic-acid dissociation constants of Mehrbach et al., 1973 (Limnol. Oceanogr., 18: 897–907) have been derived from their experimental data and used to calculate apparent solubility product, K′sp, K′sp at 25°C and 35‰ salinity, was found to be K′sp = 4.70 × 10?7(mol2kgseawater?2) An equation was fitted to the experimental data, resulting in pK′sp = 6.5795 ? 3.7159 × 105(TS) + 0.91056(T/S) ? 22.110(1.0/S)The mean activity coefficients, , were calculated at various temperatures and salinities, using the thermodynamic solubility product of Jacobson and Langmuir, 1974 (Geochim. Cosmochim. Acta, 38: 301–318) and the apparent solubility products quoted in their paper. The change in K′sp at each salinity, as a function of temperature, was used to calculate the apparent enthalpy of dissociation for calcite, ΔH′, and the extrapolated value of ΔH0 was in good agreement with that of Jacobson and Langmuir. Finally, this work was used to calculate saturation profiles for oceanic stations and as a basis for comment of the accuracy of in-situ saturometry, as well as the applicability of in-situ K′sp pressure corrections. 相似文献
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18.
螺旋列板——深水立管涡激振动抑制装置 总被引：4，自引：0，他引：4
立管是海洋油气开采中必不可少的组成部分,它承担着流体输送和钻探的重要功能。深水立管在来流作用下容易产生涡激振动,涡激振动是造成立管疲劳破坏的主要原因之一,它会加速立管的疲劳破坏,因此需要采取适当的措施抑制深水立管涡激振动。海洋工程中涡激振动的削弱方法多是在立管外侧添加抑制装置,螺旋列板作为一种广泛应用的深水立管涡激振动抑制装置,在墨西哥湾、北海、西非等深水项目中有多年的应用。文中介绍了螺旋列板的设计、加工制作及安装方法,着重阐述了列板形状尺寸、海洋生物、包覆比例等对其抑制效率的影响,最后对螺旋列板的未来发展方向进行了展望。 相似文献
19.
Patrick S. Ditty Carol J. Harmon Orrin H. Pilkey Mahlon M. Ball Evan S. Richardson 《Marine Geology》1977,24(1):1-20
Sedimentation in the 9500 km2, 4100 m deep Hispaniòla—Caicos Basin is dominated by turbidity currents. Carbonate turbidites originate from the Bahama Islands, Great Inagua and Caicos at the north end of the basin. Mixed carbonate—non-carbonate flows come from Hispaniola and perhaps Cuba. Most flows originate on insular slopes rather than in shallow water. The relatively low CaCO3 content of hemipelagic sequences throughout the entire basin reveals that the influence of non-carbonate Hispaniola—Cuba sources is widespread.The basin was sampled with closely spaced piston cores. Sand-layer isopach and frequency maps reveal four or five major basin entry points for turbidity currents. Flow size is proportional to the size of source areas. Average volumes of flows originating from Hispaniola—Cuba, the largest source, are 109 m3. This compares to an average flow volume of 106 m3 for flows derived from the smallest source area, the Southeastern Caicos Bank. Measures of turbidity-current activity, such as thickness and frequency, change in a regular fashion away from each entry point. Average lutite thickness (combining hemipelagic and turbiditic lutite) are greatest near the basin entry points. On the abyssal plain occupying the south half of the basin, Bouma turbidite sedimentary structure sequences tend to be complete. However, on the Caicos Fan, the sedimentary structure sequences in turbidites are characterized by missing or repeated units. Six radiocarbon dates of two widespread presumed pelagic units in the basin yielded younger dates in stratigraphically older positions. The reversed dates are assumed to reflect storm erosion of older sediment on adjacent insular shelves.Consideration of a north—south reflection seismic profile over the basin indicates that the present sediment regimen has pertained through much of the Neogene. The coherence, convergence and termination of reflections in the seismic section are consistent with and tend to confirm conclusions based on the core study regarding the greater extent and volume of sediment deposits derived from the Hispaniola source area. 相似文献
20.
杜氏藻是目前生产天然β-胡萝卜素最好的商品化微藻,其β-胡萝卜素含量最高达细胞干重的14%(质量分数)。此外,通过紫外线或化学诱变剂处理,也能获得用来生产八氢番茄红素、番茄红素、叶黄素和玉米黄素等其他类胡萝卜素突变株。为使杜氏藻类胡萝卜素商业开发顺利进行,分析光、温度、pH值、营养、天敌等养殖条件对杜氏藻生长和类胡萝卜素积累的影响;比较大型开放池、循环池、回旋池、级联池、大罐、异养发酵罐及封闭式光合反应器等养殖方式的利弊;同时,总结培养液再循环、藻体采集、藻泥干燥、类胡萝卜素提取等藻体采收的有益经验。 相似文献